Rheolytic thrombectomy catheter and method of using same

ABSTRACT

A surgical device and method for removal of tissue, such as thrombus, from a vessel in the body. The device has a first tube with a distal open end and an inward directed stop and a second tube with an outward directed stop for engaging the inward directed stop and thereby regulating the relationship between a retrograde jet and the distal open end. Thrombus is dislodged, entrained, and broken into pieces which are evacuated through the first tube.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a rheolytic thrombectomy catheter andmethod of using same to remove thrombus from a body vessel or other bodycavity.

2. Description of the Prior Art

Procedures and apparatus have been developed for ease in removing tissueand various deposits. Several such devices employ a jet of saline as theworking tool to help break up the tissue deposit and further provide asuction means to remove the deposit. U.S. Pat. No. 5,135,482 to Neracherdescribes a hydrodynamic device for removal of organic deposit from ahuman vessel. A supply of saline is delivered by a high pressure duct tothe distal end of a catheter. The saline exits the duct as a jet that isdirected generally forward and directly toward the tissue to be brokenup. The duct is contained within and can move axially with respect to ahose that is positioned around the duct. A vacuum suction is applied tothe hose to remove the debris that is created from the broken-up tissue.This device is not intended to pass through tortuous pathways found inthe fragile vessels of the brain, and any attempt to employ the devicefor such purpose would be far too traumatic to the patient.

Another drainage catheter, described by Griep in U.S. Pat. No.5,320,599, has a discharge channel and a pressure channel. The channelsare formed into a single catheter tube such that the two tubes are fixedwith respect to each other. This catheter could not provide theflexibility needed to negotiate the tortuous vascular pathways found inthe vessels of the brain.

SUMMARY OF THE INVENTION

The general purpose of the present invention is to provide a rheolyticthrombectomy catheter and method of using same to remove thrombus from abody vessel or other body cavity.

The present invention, a rheolytic thrombectomy catheter, is a surgicaldevice for removal of material such as thrombus from a vessel or otherbody cavity. As shown in one or more embodiments, a rheolyticthrombectomy catheter for removing tissue from a vessel or other bodycavity includes an outer assembly comprising a first tube or guidecatheter having a lumen with an open distal end and an internally anddistally located stationary stop partially obstructing the lumen at theopen distal end, the lumen being of a diameter sufficient to allowpassage of a guidewire; and an inner assembly comprising a high pressuresecond tube or hypo-tube having a high pressure lumen and a distal endhaving one or more orifices, a distally located transitional stop fixedto the high pressure hypo-tube adjacent to the distal end, and meanscharacterized as a jet cap positioned at and coacting with the hypo-tubedistal end for directing one or more jets of saline toward the distalend of the guide catheter, the inner assembly being movable axiallywithin the outer assembly such distally located transitional stopengages the stationary stop to hold the jet cap in a desiredrelationship with respect to the distal end of the guide catheter.

In another embodiment, a rheolytic thrombectomy catheter for removingthrombus or other body tissue from an obstructed body vessel or otherbody cavity includes an outer assembly including an evacuation tubehaving a proximal end and an open distal end containing a distallylocated stationary stop and having an evacuation lumen that is of adiameter sufficient to allow passage of a standard coronary orinterventional neuroradiological guidewire; and an inner assemblyincluding a high pressure hypo-tube having a high pressure lumen, thehigh pressure hypo-tube having a proximal end and a distal end, thedistal end having one or more orifices through which saline can exitfrom the high pressure lumen to be directed toward the open distal endof the evacuation tube, a transitional stop fixed to the high pressurehypo-tube at a position closer to the distal end than to the proximalend, and and means characterized as a jet cap positioned at the distalend of the high pressure hypo-tube, the jet cap coacting with the highpressure hypo-tube to direct one or more jets of saline toward the opendistal end of the evacuation tube.

Preferably, the rheolytic thrombectomy catheter has a guidewire coilattached at the distal end of the jet cap to allow advancement of theinner assembly and the outer assembly together within the vasculature.Preferably, the rheolytic thrombectomy catheter has a jet cap whichdirects a jet of saline toward the distal end of the guide catheter,which functions as an evacuation tube. Preferably, the rheolyticthrombectomy catheter includes a high pressure hypo-tube with at leastone orifice and a jet cap configured and arranged for directing one ormore jets of saline to impinge upon or near the distal end of the guidecatheter. The rheolytic thrombectomy catheter preferably is flexible andcan pass over a standard guidewire through tortuous vascular pathways.

The present invention also provides a method of removing thrombus froman obstructed body vessel. The method includes the steps of:

a. providing a guidewire and an outer assembly including a guidecatheter having a distal end and an internally located stationary stoppositioned adjacent to the distal end;

b. advancing the guidewire to a vascular site containing thrombus;

c. advancing the guide catheter over the guidewire to the vascular sitecontaining thrombus to position the distal end at the vascular site;

d. removing the guidewire from the guide catheter;

e. providing an inner assembly including a hypo-tube carrying a jet capand a transitional stop spaced apart from the jet cap;

f. advancing the inner assembly within the guide catheter of the outerassembly to engage the transitional stop with the stationary stop; and,

g. providing a high pressure saline supply to the hypo-tube so as tocause a jet of saline to emanate from the jet cap and to impinge onthrombus and on or near the distal end of the guide catheter, therebydislodging thrombus and entraining thrombus into the saline jet andthence into the guide catheter.

In the method, preferably, the jet cap carries a distally projectingguidewire coil to facilitate further distal advancement of the innerassembly and the outer assembly together within the vasculature to afurther vascular site containing thrombus so as to remove additionaldistally situated thrombus.

The present invention is also a catheter combination including a firsttube or guide catheter, being a part of an outer assembly, the firsttube having a proximal end, an open distal end, and a lumen extendingbetween the proximal end and the open distal end; a second tube orhypo-tube, being a part of an inner assembly, the second tube beingseparable from the first tube and being insertable within the lumen ofthe first tube, the second tube having a proximal end, a distal end, anda lumen extending between the proximal end and the distal end; a jetcap, being also a part of the inner assembly, the jet cap beingconnected to the second tube at the distal end of the second tube fordirecting fluid exiting the lumen of the second tube, the jet cap beingcapable of passage through the lumen of the first tube and beingcharacterized by the ability to provide a localized region of lowpressure associated with a liquid flow directed generally proximally andinto the lumen of the first tube through the open distal end of thefirst tube when the jet cap is located and oriented appropriatelyrelative to the open distal end of the first tube; and means forindexing an appropriate positional relationship of the jet cap anddistal end of the second tube relative to the open distal end of thefirst tube. The means for indexing preferably includes a distallylocated stationary stop projecting inward from the first tube and adistally located transitional stop projecting outward from the secondtube. When the second tube is advanced within the first tube, the stopsmutually engage to control the orientation and spacing and relationshipbetween the jet cap and the open distal end of the first tube. Morepreferably, the stops are each tapered to additionally laterallyposition the second tube within the first tube. Most preferably, thecentering causes the tubes to become concentric. Preferably, one or bothstops interact, when engaged, to preserve a channel for fluid flowrather than fully obstructing the cavity between the first tube and thesecond tube.

One significant aspect and feature of the present invention is thevariously designed jet caps which are oriented to direct jets of salinein a proximal direction.

Another significant aspect and feature of the present invention is thestationary stop at the distal end of the guide catheter and the distallylocated transitional stop on the hypo-tube which together coact toposition a jet cap at a defined distance beyond the distal end of theguide catheter.

Still another significant aspect and feature of the present invention isthe distally located transitional stop which has an evacuation lumen anda hypo-tube receiving hole which is offset from the longitudinal axis ofthe distally located transitional stop.

Yet another significant aspect and feature of the present invention isthe provision of complementary angled surfaces on the distally locatedstationary and transitional stops which upon engagement serve to centerthe inner assembly within the outer assembly.

A further significant aspect and feature of the present invention is thedistally located stationary stop which is formed unitarily with the wallof the guide catheter at the distal end of the guide catheter.

A still further significant aspect and feature of the present inventionis the guidewire coil provided at the distal end of the jet cap to allowadvancement of the inner assembly and the outer assembly together withinthe vasculature.

Having thus described embodiments and significant aspects and featuresof the present invention, it is the principal object of the presentinvention to provide a rheolytic thrombectomy catheter and method ofusing same to remove thrombus from a body vessel.

One object of the present invention is to provide a rheolyticthrombectomy catheter of such size, flexibility and construction as toenable it to pass readily through the tortuous pathways found in thefragile vessels of the brain.

Another object of the present invention is to provide a rheolyticthrombectomy catheter with means for producing one or more jets ofsaline and projecting them in a proximal direction toward a site ofthrombus and toward an evacuation passage.

Yet another object of the present invention is to provide a rheolyticthrombectomy catheter with means for producing one or more jets ofsaline and with indexing means to position the jet producing means at aprescribed location at the distal end of the catheter.

Still another object of the present invention is to provide a rheolyticthrombectomy catheter of the type having an inner assembly that isinsertable into an outer assembly with stop means for limiting theextent to which the inner assembly can be inserted into the outerassembly.

A further object of the present invention is to provide a rheolyticthrombectomy catheter of the type having an inner assembly and an outerassembly with means which centers the inner assembly within the outerassembly and which orients the parts of the inner assembly in aprescribed manner with respect to the parts of the outer assembly.

A still further object of the present invention is to provide animproved method of removing thrombus from an obstructed body vessel.

BRIEF DESCRIPTION OF THE DRAWINGS

Other objects of the present invention and many of the attendantadvantages of the present invention will be readily appreciated as thesame becomes better understood by reference to the following detaileddescription when considered in connection with the accompanyingdrawings, in which like reference numerals designate like partsthroughout the figures thereof and wherein:

FIG. 1 is a side view of the present invention, a rheolytic thrombectomycatheter useful for the removal of thrombus;

FIG. 2 is a semi-exploded side view of the rheolytic thrombectomycatheter depicting the two major assemblies thereof, viz., an outerassembly and an inner assembly;

FIG. 3 is a semi-exploded cross sectional side view of a manifold andadjacent components constituting parts of the outer assembly;

FIG. 4 is a longitudinal sectional view of a filter housing/highpressure connection assembly attached to the proximal end of ahypo-tube, shown only partially;

FIG. 5 is a side view of a transitional stop, a jet cap, and a guidewirecoil aligned over and about the hypo-tube at the distal end thereof;

FIG. 6 is an isometric view of the transitional stop;

FIG. 7 is a longitudinal sectional view taken along line 7--7 of FIG. 5;

FIG. 8 is a view of the proximal end of the jet cap on the hypo-tubelooking in the direction of line 8--8 of FIG. 7, with the hypo-tubeshown in cross section;

FIG. 9 is a view similar to FIG. 8 illustrating a slightly modifiedversion of the jet cap;

FIG. 10 is a longitudinal sectional view of the guide catheter distalend taken along line 10--10 of FIG. 2;

FIG. 11 is a longitudinal sectional view of the guide catheter distalend with the transitory stop, the jet cap, and the guidewire coil on thehypo-tube shown advancing therethrough;

FIG. 12 is a longitudinal sectional view of the guide catheter distalend with the transitory stop, the jet cap, and the guidewire coil on thehypo-tube shown in final advanced position;

FIG. 13 is a cross-sectional view taken along line 13--13 of FIG. 12;

FIG. 14 is presented to illustrate schematically the mode of operationof the rheolytic thrombectomy catheter, and is a longitudinal sectionalview depicting the distal end of the rheolytic thrombectomy catheterwithin a blood vessel at the site of a thrombotic deposit and lesion;

FIG. 15 is a longitudinal sectional view similar to FIG. 7 butillustrating an alternative jet cap embodiment;

FIG. 16 is a view of the proximal end of the alternative jet capembodiment shown in FIG. 15 looking in the direction of line 16--16 ofFIG. 15, with the hypo-tube shown in cross section;

FIG. 17 is a longitudinal sectional view similar to FIG. 15 butillustrating another alternative jet cap embodiment;

FIG. 18 is a view of the proximal end of the alternative jet capembodiment shown in FIG. 17 looking in the direction of line 18--18 ofFIG. 17, with the hypo-tube shown in cross section;

FIG. 19 is a longitudinal sectional view similar to FIG. 12 butillustrating an alternative transitional stop embodiment;

FIG. 20 is a view of the guide catheter distal end looking in thedirection of line 20--20 of FIG. 19, with the hypo-tube shown in crosssection;

FIG. 21 is a view similar to FIG. 12 but illustrating alternativeembodiments of the transitional stop and the stationary stop;

FIG. 22 is a view of the guide catheter distal end looking in thedirection of line 22--22 of FIG. 21, with the hypo-tube shown in crosssection; and,

FIG. 23 is a side view in partial cross section of a fifth alternativeembodiment of the guide catheter distal end, where the hypo-tube isfixed along the longitudinal axis of the guide catheter.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 illustrates a side view of a rheolytic thrombectomy catheter 10useful for the removal of thrombus, and FIG. 2 illustrates asemi-exploded side view of the rheolytic thrombectomy catheter 10. Therheolytic thrombectomy catheter 10 includes two major assemblies:namely, an outer assembly 12 and an inner assembly 14. The innerassembly 14 aligns concentrically to and within the outer assembly 12and extends beyond the length of the outer assembly 12. Externallyvisible components, or portions of components, of the outer assembly 12of the rheolytic thrombectomy catheter 10, as illustrated in FIGS. 1 and2, include a manifold 16, also known as a Y-adapter, a hemostasis nut 18secured in the proximal end 20 of the manifold 16, a Luer connection 22located at the proximal end 23 of an angled manifold branch 24 extendingfrom the manifold 16, a Luer fitting 26 secured to the distal end 28 ofthe manifold 16, a strain relief 30 secured to the distal end 28 of themanifold 16 by the Luer fitting 26, and a first tube or guide catheter32, having a distal end 33, secured to the manifold 16 by the strainrelief 30 and Luer fitting 26. The externally visible components of theinner assembly 14, illustrated in FIG. 2, include a high pressure secondtube or hypo-tube 34, a filter housing/high pressure connection assembly36 concentrically aligned to and secured over and about the hypo-tubeproximal end 38, a configured transitional stop 40 concentricallyaligned to and secured over and about the hypo-tube 34 at a point nearand adjacent to the hypo-tube distal end 42, a jet cap 44 concentricallyaligned to and secured over and about the hypo-tube 34 at the hypo-tubedistal end 42, and a guidewire coil 46 concentrically aligned to andsecured to one end of the jet cap 44. The high pressure hypo-tube 34 isdrawn and is tapered in incremental steps to provide degrees offlexibility along its length. For purposes of example and illustration,the hypo-tube 34 can include a hypo-tube portion 34a at the hypo-tubeproximal end 38 having an outer diameter of 0.018 inch or smaller, andcan include a plurality of incrementally stepped down hypo-tube portions34b-34n each of lesser outer diameter, where the last hypo-tube portion34n is stepped down to an outer diameter .008 inch at the hypo-tubedistal end 42. The hypo-tube 34 becomes increasingly more flexible fromthe hypo-tube proximal end 38 towards the hypo-tube distal end 42 due tothe incremental diameter decrease along its length. Increasingflexibility along the length of the hypo-tube 34 allows for easierflexed penetration into tortuous vascular paths. Although the hypo-tube34 is stepped down in increments, the hypo-tube 34 can also be fashionedof a constantly decreasing outer diameter to provide increasingflexibility along its length and shall not be construed to be limitingto the scope of the invention.

FIG. 3 illustrates a semi-exploded cross sectional side view of themanifold 16 and adjacent components, where all numerals correspond tothose elements previously described. The manifold 16 includes a taperedcentrally located passage 48 aligned along the longitudinal axis of themanifold 16 and a branch passage 50 extending along the axis of thebranch 24 which intersects and is connected to the central passage 48.The manifold proximal end 20 houses a multi-radius cavity 52 including around outer cavity portion 54 and a connected round inner and smallercavity portion 56 having a threaded surface 58 on the proximal portionthereof. The hemostasis nut 18 includes a body 62 having a graspingsurface 64 extending thereabout, a threaded surface 66 extending fromthe body 62, an annular surface 63 at the end of the threaded surface66, and a passageway 68 aligned centrally to the longitudinal axis ofthe hemostasis nut 18. The passageway 68 has a wide radius at theproximal end which decreases toward the distal end. The initial wideradius is helpful for insertion of the inner assembly 14 or guidewiresand the like. A seal 60 aligns to the distally located annular surface61 of the round inner cavity portion 56 and bears against the annularsurface 63 of the hemostasis nut 18 to seal the central passage 48 ofthe manifold 16 to the passageway 68 in the hemostasis nut 18. Themulti-radius cavity 52 and its internal geometry accommodatecorresponding geometry of the hemostasis nut 18 and the seal 60. Luerconnection 22 extends from the angled manifold branch proximal end 23. Afilter 72 aligns at the mouth of the branch passage 50. The filter 72and a Luer fitting (not illustrated) can be used to prevent anyparticulate outflow, to provide for metered outflow, or, alternatively,to provide suction for fluid or particle evacuation.

Luer fitting 26 is utilized to secure the strain relief 30 and the guidecatheter 32 to the distal manifold end 28. The strain relief 30 iscomprised of a tube 31, a central bore 74 internal to the tube 31 whichaccommodates the guide catheter 32, an annular flange 76 about the tube31, and a tapered proximal tube mouth end 78. It is noted that the outerdiameter of the tube 31 is constant from the annular flange 76 to thedistal tube end 80, and that the outer diameter steadily decreases fromthe annular flange 76 to the tapered proximal tube mouth end 78 toprovide a tapered tube surface 82 which conforms, for purpose of aproper fit, to the taper of the tapered central passage surface 88 ofthe central passage 48. The tapered proximal tube mouth end 78 allowsfor easily accomplished alignment of guidewires and other assemblies,such as inner assembly 14 and the like, with a lumen 87 located in theguide catheter 32. The Luer fitting 26 includes threads 84 whichthreadingly engage corresponding threads 86 at the distal end 28 of themanifold 16. The Luer fitting 26 bears against the annular flange 76 ofthe strain relief 30 to force the tapered tube surface 82 of the strainrelief 30 against the tapered central passage surface 88 of the centralpassage 48 to effect a suitable seal.

FIG. 4 illustrates a longitudinal sectional view of the filterhousing/high pressure connection assembly 36 located at the hypo-tubeproximal end 38 of the hypo-tube 34, where all numerals correspond tothose elements previously described. The filter housing/high pressureconnection assembly 36 includes a cylindrical-like body 90 having athreaded surface 92, a tubular cavity 94, fine and course filters 96 and98 residing in the tubular cavity 94, a central passage 100 extendingthrough the body 90 and connecting to the tubular cavity 94, and aplug-like cap 102, having a central bore 104, extending into the tubularcavity 94 of the body 90. The hypo-tube 34 suitably secures within thecentral bore 104 of the cap 102. The central passage 100 communicatesthrough fine and course filters 96 and 98 with the lumen 106 of thehypo-tube 34.

FIG. 5 illustrates a side view of the transitional stop 40, the jet cap44 and the guidewire coil 46 aligned over and about the hypo-tube 34near or at the hypo-tube distal end 42, where all numerals correspond tothose elements previously described. The relative sizes of thetransitional stop 40 and the jet cap 44 with respect to each other andwith respect to the sizes of the lumen 87 of the guide catheter 32 and astationary stop 150 residing in the guide catheter 32, as well asdetails of the transitional stop 40, are discussed in detail below withrelation to FIGS. 6, 12 and 13.

FIG. 6 illustrates an isometric view of the transitional stop 40, whereall numerals correspond to those elements previously described. Theone-piece transitional stop 40 includes a tubular body 108 having acentral bore 110 and a plurality of guide bars 112a-112n extendingradially from the tubular body 108. Guide bars 112a-112n include angledleading edges 114a-114n extending from the leading portion of the body108 to arced surfaces 116a-116n. The angled leading edges 114a-114ncontact a stationary stop 150 in the guide catheter 32, as laterdescribed in detail. Preferably, and for purposes of example andillustration, the arced surfaces 116a-116n describe arcs centered on thelongitudinal axis of the tubular body 108; but, in the alternative, thearced surfaces 116a-116n could describe arcs having other centers, orthe surfaces could be flat or be of other geometric design, and shallnot be construed to be limiting to the scope of the invention.

FIG. 7 illustrates a longitudinal sectional view, taken along line 7--7of FIG. 5, of the transitional stop 40, the jet cap 44 and the guidewirecoil 46 aligned and secured over and about the hypo-tube 34 near or atthe hypo-tube distal end 42; and FIG. 8 illustrates a view of the jetcap 44 looking in the direction of line 8--8 of FIG. 7, where allnumerals correspond to those elements previously described. The centralbore 110 of the transitional stop 40 is aligned and appropriatelysecured over and about the last hypo-tube portion 34n to affix thetransitional stop 40 over and about and near the hypo-tube distal end42. The proximal end of the transitional stop 40 juxtaposes and abutsthe shoulder-like transition 117 between the next to the last hypo-tubeportion 34g and the last hypo-tube portion 34n. The jet cap 44 alignsover and about and is secured to the last hypo-tube portion 34n at thehypo-tube distal end 42. As shown in FIGS. 7 and 8, the jet cap 44 istubular and includes a circular peripheral wall 118 and a circular endwall 120 extending inwardly from one end of the circular peripheral wall118. Central to the circular end wall 120 is an elongated hole 122having arcuate ends and opposite sides each having an arcuate midsection and straight portions extending oppositely from the arcuate midsection to the opposite arcuate ends, as shown in FIG. 8. The arcuatemid sections of the opposite sides of the elongated hole 122 arepositioned at the center of the elongated hole 122 and are defined byopposing aligned arcuate portions 124 and 126 of common radius. The lasthypo-tube portion 34n aligns to and extends through the center of theelongated hole 122 and is embraced by the arcuate portions 124 and 126,thereby dividing the elongated hole 122 into two jet orifices 128 and130, the jet orifice 128 being defined by the portion of elongated hole122 to one side of the outer surface of the last hypo-tube portion 34n,and the jet orifice 130 being defined by the portion of elongated hole122 to the other side of the outer surface of the last hypo-tube portion34n. At the distal end of the circular peripheral wall 118 is a weld 132which joins together the circular peripheral wall 118, the extreme tipof the distal end 42 of the hypo-tube 34, the guidewire coil 46 and atapered core 134. A plurality of orifices including orifices 136 and 138in the distal end 42 of hypo-tube 34 align within the central cavity 140of the jet cap 44 for fluid communication from lumen 106 to the centralcavity 140 and to the two jet orifices 128 and 130. A weld 142 is alsoincluded at the distal end of the guidewire coil 46 to secure the end ofthe tapered core 134 to the guidewire coil 46 and to provide for smoothentry into a vessel or other body cavity.

FIG. 9 illustrates a slightly modified version of the jet cap 44 whereintwo distinct jet orifices 144 and 146 are included in the circular endwall 120 in lieu of the elongated hole 122 shown in FIG. 8, and whereina bore 148 in the circular end wall 120 accommodates the last hypo-tubeportion 34n.

FIG. 10 illustrates a longitudinal sectional view of the guide catheterdistal end 33 of the guide catheter 32 taken along line 10--10 of FIG.2, where all numerals correspond to those elements previously described.Illustrated in particular is the multi-radiused stationary stop 150frictionally engaging the lumen 87 at the guide catheter distal end 33.One outer radius defines the cylindrical body 152, which frictionallyengages lumen 87, and another larger outer radius defines a cap 153 atthe end of the stationary stop 150. A central bore 154 aligns coaxiallywithin the cylindrical body 152 and the cap 153. An annular shoulder 156between the cap 153 and the cylindrical body 152 abuts and aligns to theguide catheter distal end 33. An angled annular surface 158, which iscomplementary to the angled leading edges 114a-114n of the transitionalstop 40 shown in FIG. 6, is included at the proximal end of thecylindrical body 152. An annular crimp sleeve 160 applied over and aboutthe guide catheter distal end 33 ensures a positive fixation of thestationary stop 150 in the lumen 87.

FIG. 11 illustrates a longitudinal sectional view of the guide catheterdistal end with the jet cap 44 transiting the central bore 154 of thestationary stop 150 and with the transitional stop 40 aligned within thelumen 87 of the guide catheter 32, where all numerals correspond tothose elements previously described.

FIG. 12 illustrates a longitudinal sectional view of the guide catheterdistal end with the transitional stop 40 aligned within the lumen 87 ofthe guide catheter 32 and in mutual engagement with the stationary stop150, where all numerals correspond to those elements previouslydescribed. Mutual engagement of the stationary stop 150 with thetransitional stop 40 positions the jet cap 44 at a desirable and finitedistance from the stationary stop 150 at the guide catheter distal end33.

Tubular guide catheter 32 may be constructed of a flexible polymermaterial and is characterized by an ability to follow over a flexibleguidewire through the vasculature of a patient to be treated. Since thetubular guide catheter 32 may also be subjected to reduced or vacuumpressures in some applications, the tubular guide catheter 32 should beresistant to collapse or bursting at the pressure differentialsemployed. Again, for purposes of example and illustration, the guidecatheter 32 can have an outer diameter of about 4 French or smaller, oran outer diameter of about 0.040 inch, and an inner diameter of about0.028 inch which can also taper in diameter. As is well known in theart, the guide catheter 32 may be advanced and maneuvered through thevasculature such that the guide catheter distal end 33 may beselectively positioned adjacent to the site of desired surgical action,for example, adjacent to a thrombus obstructing a blood vessel.

The stationary stop 150 may be formed from a variety of materials.Preferably, the stationary stop 150 is formed of material identical tothat of the guide catheter 32.

The transitional stop 40 is mounted in the hypo-tube 34 at a locationspaced apart from the hypo-tube distal end 42 and distal from thehypo-tube portion 34g. The transitional stop 40 has a cross sectionalextent such that it may not freely pass the stationary stop 150. Thetransitional stop 40 has a substantially X-shaped cross section whenviewed axially, as in FIG. 13, which allows for fluid passage in aproximal direction. However, as will be discussed subsequently, numerousalternative shapes might be employed for the transitional stop 40provided that at least passage of the transitional stop past thestationary stop 150 is prevented. Preferably, the distal portion of thetransitional stop 40 includes tapered surfaces, such as angled leadingedges 114a-114n. The jet cap 44 presents a cross section capable ofpassing through the central bore 154 of the stationary stop 150. Theangled leading edges 114a-114n serve, in juxtaposition with the angledannular surface 158 of the stationary stop 150, to desirablylongitudinally position the transitional stop 40 relative to thestationary stop 150. The close longitudinal alignment of the pluralityof guide bars 112a-112n within the lumen 87 of the guide catheter 32generates lateral spaced relations, such as, for example, a concentricrelationship between the first tube or guide catheter 32 and the secondtube or hypo-tube 34, respectively. Preferably, the cross sectionalextent of the transitional stop 40 is roughly about 0.010 inch to about0.030 inch; however, the critical consideration in cross sectionaldimensions of the transitional stop 40 is that it must pass through thelumen 87 of the first tube or guide catheter 32 and yet not pass thestationary stop 150.

The jet cap 44 is mounted at the distal end 42 of the hypo-tube 34 andincludes a guidewire coil 46 extending distally from the jet cap 44. Ina preferred embodiment, the jet cap 44, guidewire coil 46 andtransitional stop 40 are radially symmetrical about the longitudinalextent of the hypo-tube 34. In such an embodiment, the jet cap 44preferably has a diameter of from about 0.010 inch to about 0.030 inch.The hypo-tube 34 preferably has an outer diameter of about 0.008 inch toabout 0.018 inch and also includes a continuous high pressure lumen 106extending from the hypo-tube proximal end 38 to the hypo-tube distal end42 and continuing into the jet cap 44. When the hypo-tube distal end 42of the hypo-tube 34 is advanced through the lumen 87 of the guidecatheter 32, the guidewire coil 46 and the jet cap 44 and any portion ofthe hypo-tube 34 distal from the transitional stop 40 are free to passthe location of the stationary stop 150. However, passage of thetransitional stop 40 is prevented by the partial obstruction of thelumen 87 of guide catheter 32 by the stationary stop 150. Thus, when thedistal angled leading edges 114a-114n of the transitional stop 40 engagethe angled annular surface 158 of the stationary stop 150, a desiredlongitudinal relationship is dependably generated between the jet cap 44and the guide catheter distal end 33 (at the cap 153) of the guidecatheter 32. Most importantly, the jet cap 44 is oriented and spacedapart and distally situated at a desired relationship to the guidecatheter distal end 33 of the guide catheter 32.

The jet cap 44 is preferably rounded or tapered at the distal end tofacilitate advancement of the hypo-tube 34 and to avoid catching orsnagging on the interior of the guide catheter 32, on the stationarystop 150, or on a vessel wall when advanced beyond the guide catheterdistal end 33.

Fluid communication between the lumen 87 and the central bore 154 of thestationary stop 150 is allowed longitudinally and in a distal directionabout the geometry of the transitional stop 40. As partially shown inFIGS. 5 and 6 and as fully shown in FIG. 13, longitudinally orientedpassages 162a-116n are formed. For example, passage 162a is formedbetween guide bars 112a and 112b and a portion of the periphery oftransitional stop body 108 extending from the proximal region of thetransitional stop 40 distally toward and including the angled leadingedges 114a-114b. Longitudinally oriented passages 162b-162n are formedin a corresponding fashion. Note particularly that a portion of thelumen 87 remains open where the transitional stop 40 interacts with thestationary stop 150 to allow passage of liquid and small portions ofsuspended tissue proximally through the guide catheter 32.

FIG. 13 illustrates a cross sectional view of the guide catheter distalend 33 taken along line 13--13 of FIG. 12, where all numerals correspondto those elements previously described. Illustrated in particular arethe plurality of passages 162a-162n about the transitional stop 40 whichallow passage of liquid and small portions of suspended tissueproximally through the lumen 87 of the guide catheter 32. Although theguide bars 112a-112n include planar side surfaces, other configurationshaving a rounded intersection or even having non-planar intersectingwalls or other variations of longitudinal passages can be utilized andshall not be construed to be limiting to the scope of the invention.

Mode of Operation

FIG. 14 best illustrates the mode of operation of the rheolyticthrombectomy catheter 10 with particular attention to the guide catheterdistal end 33 and jet cap 44 positioned in a blood vessel 164, artery orthe like at the site of a thrombotic deposit and lesion 166.

A guidewire is first advanced percutaneously through the vasculature tothe site of the thrombotic deposit and lesion 166. For a distal coronaryvessel or a vessel of the brain, typically the guidewire has a diameterof 0.010-0.016 inch. This invention can also be applied to largervessels which require larger diameter guidewires. Once a guidewire hasbeen advanced along the vessel 164 and has reached the thromboticdeposit and lesion, guide catheter 32, the first tube, which serves as aflexible evacuation tube, can be advanced over the guidewire throughtortuous turns to reach the thrombotic deposit and lesion. With theguide catheter distal end 33 of the guide catheter 32 positioned nearthe thrombotic deposit and lesion 166, the guidewire can then be removedfrom the guide catheter 32 and the patient's body. The jet cap 44 at theterminus of the second tube or hypo-tube 34 is then advanced within thelumen 87 of the guide catheter 32 until the transitional stop 40contacts the stationary stop 150 of the guide catheter 32.

The arced surfaces 116a-116n at the extremities of the guide bars112a-112n of the transitional stop 40 provide for guidance of thetransitional stop 40 along the lumen 87 and also center the jet cap 44in the center of the guide catheter 32 during initial transition andprovide for centering of the jet cap 44 in the central bore 154 of thestationary stop 150 prior to engagement of the transitional stop 40 withthe stationary stop 150. Engagement of the angled leading edges114a-114n with the stationary stop 150 sets a predetermined gap ordistance from the jet cap 44 proximal end to the stationary stop 150.The central bore 154 and lumen 87 of the guide catheter 32 serve as anevacuation tube at the guide catheter distal end 33. The rheolyticthrombectomy catheter 10 can then be activated by providing highpressure liquid, preferably saline, to the proximal end of the guidecatheter 32 via the manifold 16.

High pressure saline, or other liquid, from the manifold 16 is providedand flows through the lumen 106 of the hypo-tube 34 to exit orifices 136and 138 leading to the central cavity 140 of the jet cap 44. The highpressure saline exits jet orifices 128 and 130 as retrograde jets 170 ofhigh velocity saline being directed toward the open central bore 154 inthe stationary stop 150 at the guide catheter distal end 33. The highvelocity saline jets 170 dislodge tissue from the thrombotic deposit andlesion 166 and entrain it into the saline jets 170 where it is broken upinto smaller fragments. Impingement of the saline jets 170 onto theguide catheter distal end opening creates a stagnation pressure withinthe evacuation lumen 87 that drives the debris particles of tissue fromthe thrombotic deposit and lesion 166 toward the proximal end of theguide catheter 32.

A positive displacement piston PUMP (not illustrated) can be used toprovide liquid, preferably saline, under pressure to the proximal end ofthe hypo-tube 34. A pressure ranging from 500-15,000 psi will providethe energy to create a useful high velocity jet as the saline exits thejet orifices 128 and 130 located at the circular end wall 120 of the jetcap 44. The flow rate of saline can be controlled by adjusting thepumping rate of the positive displacement pump. The proximal end of theguide catheter 32 interfaces with a suction device through the Luerconnection 22 at the manifold branch 24, for example, a roller pump,prior to discharge of the evacuated thrombotic debris into a collectionbag for disposal. The rate of evacuation can be controlled by adjustingthe rate of the roller pump. The rate of saline inflow can be balancedwith the rate of removal of thrombotic debris by simultaneous adjustmentof the piston pump and the roller pump. The rate of saline inflow can beless than, equal to, or greater than the rate of removal of thromboticdebris. The rate of thrombus removal can be set to slightly exceed therate of saline inflow to reduce the likelihood for distal embolizationof thrombotic tissue.

Alternative Embodiments

FIG. 15, a first alternative embodiment, illustrates a longitudinalsectional view of the transitional stop 40, an alternative jet cap 180,in lieu of jet cap 44, and a guidewire coil 46a aligned and secured overand about the hypo-tube 34 near or at a hypo-tube distal end 42a; andFIG. 16 illustrates a view of the jet cap 180 looking in the directionof line 16--16 of FIG. 15, where all numerals correspond to thoseelements previously described. The jet cap 180 includes several likecomponents as described previously. The jet cap 180 aligns over andabout and is secured to the last hypo-tube portion 34na, which anglesdownwardly from the longitudinal axis of the hypo-tube 34 at thehypo-tube distal end 42a. The jet cap 180 is tubular and includes acircular peripheral wall 118a and a circular end wall 120a extendinginwardly from one end of the circular peripheral wall 118a. Located inthe circular end wall 120a are two holes 182 and 184 which support aU-shaped hypo-tube portion 34x extending from the last hypo-tube portion34na. The U-shaped hypo-tube portion 34x aligns to and extends throughthe holes 182 and 184 in the circular end wall 120a, as well as throughthe jet cap central cavity 140a. The free end portion of the U-shapedhypo-tube portion 34x secures in the hole 184 flush with the circularend wall 120a and is open, thereby defining an orifice aligned to directa high velocity jet stream, preferably saline, in a proximal directionin a manner and fashion such as previously described. At the distal endof the circular peripheral wall 118a is a weld 132a which joins togetherthe circular peripheral wall 118a, the bight of the U-shaped portion 34xof the hypo-tube 34, the guidewire coil 46a and a tapered core 134a. Aweld 142a is also included at the distal end of the guidewire coil 46ato secure the end of the tapered core 134a to the guidewire coil 46a andto provide for smooth entry into a vessel or other body cavity.

FIG. 16 is a view of the proximal end of the first alternative jet capembodiment looking in the direction of line 16--16 of FIG. 15, where allnumerals correspond to those elements previously described.

FIG. 17, a second alternative embodiment, illustrates a longitudinalsectional view of the transitional stop 40, an alternative jet cap 200,in lieu of jet cap 44, and a guidewire coil 46b aligned and secured overand about the hypo-tube 34 near or at a hypo-tube distal end 42b; andFIG. 18 illustrates a view of the jet cap 200 looking in the directionof line 18--18 of FIG. 17, where all numerals correspond to thoseelements previously described. The jet cap 200 includes several likecomponents as described previously. The jet cap 200 aligns over andabout and is secured to the last hypo-tube portion 34nb, which anglesdownwardly from the longitudinal axis of the hypo-tube 34 at thehypo-tube distal end 42b. The jet cap 200 is tubular and includes acircular peripheral wall 118b and a circular end wall 120b extendinginwardly from one end of the circular peripheral wall 118b. Located inthe circular end wall 120b is a hole 202, and, preferably, a centrallylocated jet orifice 206. Preferably one jet orifice is included,although more jet orifices can be utilized and shall not be deemed aslimiting to the scope of the invention. The last hypo-tube portion 34nbaligns to and extends through the hole 202 in the circular end wall 120band has an open end or orifice which ends in the jet cap central cavity140b of the jet cap 200 for fluid communication from lumen 106 to thecentral cavity 140b and to the jet orifice 206 to direct a high velocityjet stream, preferably saline, in a proximal direction in a manner andfashion such as previously described. At the distal end of the circularperipheral wall 118b is a weld 132b which joins together the circularperipheral wall 118b, the guidewire coil 46b and a tapered core 134b. Aweld 142b is also included at the distal end of the guidewire coil 46bto secure the end of the tapered core 134b to the guidewire coil 46b andto provide for smooth entry into a vessel or other body cavity.

FIG. 18 is a view of the proximal end of the second alternative jet capembodiment looking in the direction of line 18--18 of FIG. 17, where allnumerals correspond to those elements previously described.

FIG. 19, a third alternative embodiment, illustrates a longitudinalsectional view of a transitional stop 210, a jet cap 212 being similarto the configuration of jet cap 180 of FIG. 15 and in lieu of jet cap44, and a guidewire coil 46c, being similar in configuration toguidewire coil 46a, aligned and secured over and about the hypo-tube 34near or at a non-angled hypo-tube distal end 42c; and FIG. 20illustrates a view of the guide catheter distal end 33 looking in thedirection of line 20--20 of FIG. 19, where all numerals correspond tothose elements previously described. In this embodiment the jet cap 212aligns over and about and is secured to the last hypo-tube portion 34ncwhich projects straight outwardly from the lumen 87 and fromtransitional stop 210. The longitudinal axis of the hypo-tube 34 and thelast hypo-tube portion 34nc is offset from the central axis of thetransitional stop 210, at the hypo-tube distal end 42c. Having the lasthypo-tube portion 34nc located off-center obviates the requirement ofhaving a last hypo-tube portion which angles downwardly from thelongitudinal axis of the hypo-tube 34 and also allows the jet cap 212 toalign with the central bore 154 of the stationary stop 150 withouthaving an angled last hypo-tube portion. The transitional stop 210 isfashioned of a solid material having a circular cross section, one endof which is in the form of a truncated cone having an angled annularsurface 214 and also having a longitudinally oriented hole 216 distantfrom the central longitudinal axis of the transitional stop 210 and, inaddition, a longitudinally oriented lumen 218 distant from the centrallongitudinal axis of the transitional stop 210. The transitional stop210 is positioned as illustrated to position the angled annular surface214 against the angled annular surface 158 of the stationary stop 150 toposition the jet cap 212 at a desirable and finite distance from thestationary stop 150 at the guide catheter distal end 33 so that a highvelocity jet stream, preferably saline, emanating from the open end ororifice of the hypo-tube may be directed in a proximal direction in amanner and fashion toward the lumen 218 to dislodge, break up and carryaway thrombotic tissue debris, such as previously described.

FIG. 20 illustrates a view of the guide catheter distal end 33 lookingin the direction of line 20--20 of FIG. 19, where all numeralscorrespond to those elements previously described.

FIG. 21, a fourth alternative embodiment, illustrates a longitudinalsectional view of a guide catheter distal end 33a and havingalternatively configured stationary and transitional stops, where allnumerals correspond to those elements previously described. Located atthe guide catheter distal end 33a of the guide catheter 32 is astationary stop 230. The stationary stop 230 is permanently connectedto, molded to, or otherwise formed to the tubing wall of the guidecatheter 32 and projects into the lumen 87 of the guide catheter 32. Byprojecting inward and into the lumen 87, the stationary stop 230, beingcomprised of a plurality of arcuate stops 230a-230n, partially obstructsthe lumen 87. However, the stationary stop 230 does not fully obstructthe lumen 87. Moreover, the stationary stop 230 allows for free passageof a standard guidewire through the lumen 87 in the region adjacent theguide catheter distal end 33a of the guide catheter 32. Preferably, andfor purposes of example and illustration, the arrangement and dimensionsof the stationary stop 230 are such that a coronary or neurologicalguidewire having a diameter of at least 0.010 inch, more preferably0.016 inch, can freely pass the stationary stop 230. Most preferably,the unobstructed diameter of the stationary stop 230 is from about 0.010inch to about 0.030 inch. The guide catheter 32 has an outer diameter ofabout 0.040 inch and an inner diameter of about 0.028 inch or about 4French or smaller. As is well known in the art, the guide catheter 32may be advanced and maneuvered through the vasculature such that theguide catheter distal end 33a may be selectively positioned adjacent tothe site of desired surgical action, for example, adjacent to a thrombusobstructing a blood vessel.

The stationary stop 230 has a plurality of arcuate stops 230a-230naligned parallel to the central axis of the guide catheter 32, eachhaving a proximal tapered surface 234a-234n and a distal tapered surface236a-236n. The stationary stop 230 may be formed from a variety ofmaterials. Preferably, the stationary stop 230 is formed of materialidentical to that of the guide catheter 32. Most preferably, thestationary stop 230 is fabricated by a permanent deformation andthickening of the wall of the guide catheter 32 at the desired location.Alternatively, the stationary stop 230 might be separately constructedand then fixed within the guide catheter 32.

The hypo-tube 34, or second tube, is fashioned as previously describedhaving a hypo-tube distal end 42d and a proximal end (not shown). Atransitional stop 238 is mounted on the last hypo-tube portion 34nd at alocation spaced apart from a jet cap 240 and a guidewire coil 46d alsomounted on the last hypo-tube portion 34nd. The transitional stop 238has a cross sectional extent such that it may not freely pass thestationary stop 230. In one embodiment, the transitional stop 238 has arounded cross section when viewed axially. However, numerous alternativeshapes might be employed for the transitional stop 238 provided that atleast passage past the stationary stop 230 is prevented. Preferably, thedistal surface 242 of the transitional stop 238 is tapered, such that adistalmost extent of the transitional stop 238 presents a cross sectioncapable of passing the proximalmost extent of the stationary stop 230,generally as represented by the proximal tapered surfaces 234a-234n.Distal tapered surface 242 serves a dual function by first facilitatingpassage and advancement of the hypo-tube 34 by reducing any tendency tocatch or bind within the guide catheter 32, and second, to desirablylaterally position the transitional stop 238 relative to the stationarystop 230 and thereby generate lateral relations, such as for example, aconcentric relationship between the guide catheter 32 and hypo-tube 34,respectively. Preferably, the cross sectional extent of the transitionalstop 238 is roughly about 0.010 inch to about 0.030 inch; however, thecritical consideration in cross sectional dimensions of the transitionalstop 238 is that it must pass through the lumen 87 of the guide catheter32 and yet not pass the stationary stop 230.

As previously mentioned, a jet cap 240 is mounted at the hypo-tubedistal end 42d of the hypo-tube 34. A guidewire coil 46d extendsdistally from the jet cap 240. The jet cap 240, guidewire coil 46 andtransitional stop 238 are radially symmetrical about the longitudinalextent of the hypo-tube 34. The jet cap 240 preferably has a diameter offrom about 0.010 inch to about 0.030 inch. The hypo-tube 34 preferablyhas an outer diameter of about 0.008 inch to about 0.018 inch and alsoincludes a continuous high pressure lumen 106 extending from theproximal end to the hypo-tube distal end 42d and continuing into the jetcap 240. When the end of the hypo-tube 34 is advanced through the lumen87 of the guide catheter 32, the guidewire coil 46d adjacent the jet cap240 and any portion of the hypo-tube 34 distal from the transitionalstop 238 are free to pass the location of the stationary stop 230.However, passage of the transitional stop 238 is prevented by thepartial obstruction of the lumen 87 of guide catheter 32 by thestationary stop 230. Thus, when the distal tapered surface 242 of thetransitional stop 238 engages the proximal tapered surfaces 234a-234n ofthe stationary stop 230, a desired longitudinal relationship isdependably generated between the jet cap 240 and the guide catheterdistal end 33a. Most importantly, the jet cap 240 is oriented and spacedapart and distally situated at a desired relationship to the distal end33a of the guide catheter 32.

FIG. 22 illustrates a view of the guide catheter distal end 33a lookingin the direction of line 22--22 of FIG. 21, where all numeralscorrespond to those elements previously described. Illustrated inparticular are the plurality of arcuate stops 230a-230n shown in contactwith the distal tapered surface 242 of the transitional stop 238. Fluidscontaining thrombotic debris can pass between the arcuate stops230a-230n, along the inner wall of the guide catheter 32 which isadjacent to and between the arcuate stops 230a-230n, along thetransitional stop 238, and into the lumen 87 of the guide catheter 32for passage to the manifold 16.

FIG. 23, a fifth alternative embodiment, illustrates, in partial crosssection, a side view of the guide catheter distal end 33 where thehypo-tube 34 is fixed along the longitudinal axis of the guide catheter32, where all numerals correspond to those elements previouslydescribed. In this embodiment of a one-piece catheter, the hypo-tube 34is appropriately aligned and secured in a central bore 244 of acylindrical fixture 246 which secures in the end of the guide catheter32 by a crimp sleeve 248. A jet cap 250 and a guidewire coil 46e secureto the hypo-tube distal end 42e at the last hypo-tube portion 34ne at afixed distance from the guide catheter distal end 33. In thisembodiment, no transitional or stationary stops are incorporated, as theentire catheter system incorporating a longitudinally fixed hypo-tube 34is inserted into the body without use of a guidewire. The cylindricalfixture 246 has passages with the same profile as passages 162a-162n ofthe transitional stop 40 for connection to lumen 87 in the guidecatheter 32.

Because numerous modifications may be made to this invention withoutdeparting from the spirit thereof, the scope of the invention is not tobe limited to the embodiments illustrated and described. Rather, thescope of the invention is to be determined by the appended claims andtheir equivalents. The tip can be radio-opaque. The guidewire can be abraided polymer or other suitable material.

While each of the the parts 44, 180, 200, 212, 240, and 250 representingmeans positioned at the distal end of the high pressure tube andcoacting with the distal end of the high pressure tube for directingfluid toward the open end of the evacuation tube has been characterizedthroughout the description as a "jet cap", it is here pointed out thatthis term "jet cap" is not of common usage in the art but, rather, hasbeen introduced as a convenient expression by which to indicate thegeneral character of these parts, in that they act in the nature of acap at the distal end of the high pressure tube and serve in coactionwith the distal end of the high pressure tube to direct one or more jetsof fluid proximally toward the open distal end of the evacuation tube.Accordingly, the term "jet cap" is not to be construed in a limitingsense as defining a particular structure, but is to be regarded asmerely signifying the general nature of the instrumentally provided fordirecting fluid in the manner described.

While each of the parts 44, 180, 200, 212, 240 and 250 representingmeans positioned at the distal end of the high pressure tube andcoacting with the distal end of the high pressure tube for directingfluid toward the open end of the evacuation tube has been characterizedthoughout the description as a "jet cap", it is here pointed out thatthis term "jet cap" is not of common usage in the art but, rather, hasbeen introduced as a convenient expression by which to indicate thegeneral character of these parts, in that they act in the nature of acap at the distal end of the high pressure tube and serve in coactionwith the distal end of the high pressure tube to direct one or more jetsof fluid proximally toward the open distal end of the evacuation tube.Accordingly, the term "jet cap" is not to be construed in a limitingsense as defining a particular structure, but is to be regarded asmerely signifying the general nature of the instrumentally provided fordirecting fluid in the manner described.

It is claimed:
 1. A catheter for removing material from a body cavitycomprising:a. an outer assembly including(1) a first tube having a lumenwith an open distal end and an internally located stationary stoppartially obstructing said lumen at said open distal end and, b. aninner assembly including(1) a second tube insertable into said firsttube, said second tube having a high pressure lumen having a distal end,said distal end having an orifice; (2) a transitional stop fixed to saidsecond tube adjacent to said distal end; and, (3) means positioned atsaid distal end of said second tube and coacting with said distal end ofsaid second tube for directing fluid exiting said orifice toward saidopen distal end of said first tube, said second tube being movableaxially within said first tube such that said transitional stop engagessaid stationary stop to hold said means in a desired relationship withrespect to said open distal end of said first tube.
 2. A catheter forremoving material from a body vessel or other body cavity comprising:a.an outer assembly including(1) an evacuation tube having a proximal endand an open distal end containing a stationary stop and having anevacuation lumen; and, b. an inner assembly including(1) a high pressuretube having a high pressure lumen, said high pressure tube having aproximal end and a distal end, said distal end having one or moreorifices through which fluid can exit from said high pressure lumen tobe directed toward said open distal end of said evacuation tube; (2) atransitional stop fixed to said high pressure tube at a position closerto said distal end than to said proximal end; and, (3) means positionedat said distal end of said high pressure tube and coacting with saiddistal end of said high pressure tube to direct fluid toward said opendistal end of said evacuation tube.
 3. The catheter of claim 2, whereinsaid means has a distal end and said distal end of said jet cap has aguidewire coil attached thereto to assist in advancement of said outerassembly and said inner assembly together or separately within the bodyvessel or other body cavity.
 4. The catheter of claim 2, wherein saidmeans is configured to create a jet of fluid and to direct it towardsaid open distal end of said evacuation tube.
 5. The catheter of claim2, wherein said evacuation tube is flexible and can pass over aguidewire through tortuous pathways.
 6. A method of removing materialfrom a body vessel or other body cavity comprising the steps of:a.providing a guidewire and a first catheter having an open distal end andan internally located stationary stop positioned adjacent to the opendistal end; b. advancing the guidewire to a body cavity site containingmaterial to be removed; c. advancing the first catheter over theguidewire to the body cavity site containing material to be removed toposition the distal end at the body cavity site; d. removing theguidewire from the first catheter; e. providing a second cathetercarrying a means for directing fluid and a transitional stop spacedapart from the means for directing fluid; f. advancing the secondcatheter within the first catheter to engage the transitional stop withthe stationary stop; and, g. providing a high pressure fluid supply tothe second catheter so as to cause fluid to emanate therefrom and toimpinge upon and dislodge the material to be removed and force it intothe open distal end of the first catheter.
 7. The method of claim 6,wherein the means for directing fluid carries a distally projecting coilto facilitate further distal advancement of the first catheter and thesecond catheter together or separately within the body vessel or otherbody cavity to a further body cavity site containing material to beremoved so as to remove additional distally situated material.
 8. Acatheter combination comprising:a. a first tube having an open distalend and a lumen extending to the open distal end; b. a second tube,separable from the first tube, and insertable within the lumen of thefirst tube, the second tube having a distal end and a lumen extending tothe distal end; c. means connected to the second tube at the distal endof the second tube and coacting with the distal end of the second tubefor directing fluid exiting the lumen of the second tube, toward theopen distal end of the first tube, said means being capable of passagethrough the lumen of the first tube and being characterized by theability to provide a localized region of low pressure associated with aliquid flow directed generally proximally and into the lumen of thefirst tube through the open distal end of the first tube when locatedand oriented appropriately relative to the open distal end of the firsttube; and, d. means for indexing an appropriate positional relationshipof said means and the distal end of the second tube relative to the opendistal end of the first tube, the means for indexing comprising atransitional stop fixed to the second tube adjacent to the distal end ofthe second tube.

    ______________________________________                                        RHEOLYTIC THROMBECTOMY CATHETER AND                                           METHOD OF USING SAME                                                          PARTS LIST                                                                    ______________________________________                                        10             rheolytic                                                                     thrombectomy catheter                                          12             outer assembly                                                 14             inner assembly                                                 16             manifold                                                       18             hemostasis nut                                                 20             manifold proximal end                                          22             Luer connection                                                23             proximal end (branch)                                          24             branch                                                         26             Luer fitting                                                   28             distal manifold end                                            30             strain relief                                                  31             tube                                                           32             first tube or guide                                                           catheter                                                       33             guide catheter distal                                                         end                                                            33a            guide catheter distal                                                         end                                                            34             second tube or                                                                hypo-tube                                                      34a-n          hypo-tube portions                                             34n            last hypo-tube portion                                         34na           last hypo-tube portion                                         34ne           last hypo-tube portion                                         34nc           last hypo-tube portion                                         34nd           last hypo-tube portion                                         34x            U-shaped hypo-tube                                                            portion                                                        36             filter housing/high                                                           pressure connection assembly                                   38             hypo-tube proximal                                                            end                                                            40             transitional stop                                              42             hypo-tube distal end                                           42a            hypo-tube distal end                                           42b            hypo-tube distal end                                           42c            hypo-tube distal end                                           42d            hypo-tube distal end                                           42e            hypo-tube distal end                                           44             jet cap                                                        46             quidewire coil                                                 46a            guidewire coil                                                 46b            guidewire coil                                                 46c            guidewire coil                                                 46d            guidewire coil                                                 46e            guidewire coil                                                 48             central passage                                                50             branch passage                                                 52             multi-radius cavity                                            54             round outer cavity                                                            portion                                                        56             round inner cavity                                                            portion                                                        58             threaded surface                                               60             seal                                                           61             distal annular                                                                surface                                                        62             body                                                           63             annular surface                                                64             grasping surface                                               66             threaded surface                                               68             passageway                                                     72             filter                                                         74             central bore                                                   76             annular flange                                                 78             tapered proximal tube                                                         mouth end                                                      80             distal tube end                                                82             tapered tube surface                                           84             threads                                                        86             threads                                                        87             lumen (of 32)                                                  88             tapered central                                                               passage surface                                                90             body                                                           92             threaded surface                                               94             tubular cavity                                                 96             fine filter                                                    98             course filter                                                  100            central passage                                                102            cap                                                            104            central bore                                                   106            lumen (of 34)                                                  108            body                                                           110            central bore                                                   112a-n         guide bars                                                     114a-n         angled leading edges                                           116a-n         arced surfaces                                                 117            shoulder-like                                                                 transition                                                     118            peripheral wall                                                118a           peripheral wall                                                118b           peripheral wall                                                120            circular end wall                                              120a           circular end wall                                              120b           circular end wall                                              122            elongated hole                                                 124            arcuate portion                                                126            arcuate portion                                                128            jet orifice                                                    130            jet orifice                                                    132            weld                                                           132a           weld                                                           132b           weld                                                           134            tapered core                                                   134a           tapered core                                                   136            orifice                                                        138            orifice                                                        140            central cavity                                                 140a           central cavity                                                 140b           central cavity                                                 142            weld                                                           142a           weld                                                           142b           weld                                                           144            jet orifice                                                    146            jet orifice                                                    148            bore                                                           150            stationary stop                                                152            cylindrical body                                               153            cap                                                            154            central bore                                                   156            shoulder                                                       158            angled annular                                                                surface                                                        160            crimp sleeve                                                   162a-n         passages                                                       164            blood vessel                                                   166            thrombotic deposit                                                            and lesion                                                     170            saline jet                                                     180            jet cap                                                        182            hole                                                           184            hole                                                           200            jet cap                                                        202            hole                                                           206            jet orifice                                                    210            transitional stop                                              212            jet cap                                                        214            angled annular                                                                surface                                                        216            hole                                                           218            lumen                                                          230            stationary stop                                                230a-n         arcuate stops                                                  234a-n         proximal tapered                                                              surfaces                                                       236a-n         distal tapered                                                                surfaces                                                       238            transitional stop                                              240            jet cap                                                        242            distal tapered                                                                surface                                                        244            central bore                                                   246            cylindrical fixture                                            248            crimp sleeve                                                   250            jet cap                                                        ______________________________________                                    